The importance of Elongation and Desaturation (or, you can’t fool the body)

Palmitic acid is the most common saturated fat in our food – and in the living world. Humans (and other animals) synthesize palmitic acid from acetyl-Co A – an elementary breakdown product of carbohydrate, protein and fat metabolism. As the stem fatty acid, saturated palmitic acid (16:0) can be converted into monounsaturated oleic acid (18:1) – the most common monounsaturated fat in our food – and in the living world.

In Dr. Mary Enig’s words, fatty acid conversions are made by the body “to maintain desirable physiological balances.” Saturated fats can be converted into monounsaturated fat and, as needed, monounsaturated fats like oleic acid (18:1) can be converted back into saturated fats.

As an example, via the process of elongation, the liver and other tissues can add two additional carbons turning 16 carbon saturated palmitic into 18 carbon saturated stearic acid, which, in turn, can convert into monounsaturated oleic acid through a special process called desaturation – inserting a double bond into the chain where previously there was none.

Desaturation: 18:0 stearic becomes 18:1 oleic when a double bond is inserted into the carbon chain.

Eat a lot olive oil – and in order to maintain optimum cell membrane stiffness – the monounsaturated oleic acid will be converted into saturated fat. Eat a lot of saturated fat – in order to maintain optimum cell membrane stiffness – yur body will convert any excess into monounsaturated oleic acid.

Found abundantly throughout the living world, why would the experts in health and nutrition call palmitic acid ‘bad’?

No naturally occurring fat or oil we consume is made exclusively of either saturated or unsaturated fat. Even dominantly polyunsaturated flax oil is 9 percent saturated – containing both palmitic (16:0) and stearic acid (18:0). A totally saturated fat would be indigestible – as hard as wax – and totally unsaturated oils do not exist in our food supply.

Take-away lesson: Eat a variety of natural fats from whole foods and unrefined oils – your body will take care of the rest. For cooking, stick to the traditional more saturated and monounsaturated fats, including beef and lamb tallow (drippings), butter, coconut oil, lard (pork fat), palm oil, extra virgin olive oil, and high quality sesame oil for stir-fry.